How GDPR Enhances Transparency and Fosters Pseudonymisation in Academic Medical Research.

The European General Data Protection Regulation (GDPR) has dotted the i's and crossed the t's in the context of academic medical research. One year into GDPR, it is clear that a change of mind and the uptake of new procedures is required. Research organisations have been looking at the possibility to establish a code-of-conduct, good practices and/or guidelines for researchers that translate GDPR's abstract principles to concrete measures suitable for implementation. We introduce a proposal for the implementation of GDPR in the context of academic research which involves the processing of health related data, as developed by a multidisciplinary team at the University Hospitals Leuven. The proposal is based on three elements, three stages and six specific safeguards. Transparency and pseudonymisation are considered key to find a balance between the need for researchers to collect and analyse personal data and the increasing wish of data subjects for informational control.

Steam ablation versus radiofrequency and laser ablation: an in vivo histological comparative trial.

OBJECTIVE: There is an increasing use of minimal invasive techniques to treat saphenous vein reflux. Among these radiofrequency ablation (RFA), endovenous laser ablation (EVLA), and foam sclerotherapy are frequently used. A new method of thermal ablation is the steam vein sclerosing (SVS) system. This study evaluates the histological changes after ablation of the saphenous veins in goats with RFA, EVLA, and SVS. METHODS: Twelve saphenous veins in six goats were treated with one of the three treatment modalities: four veins with RFA, four with EVLA, four with SVS. Seven days after treatment occlusion and diameter changes were evaluated by ultrasound imaging and histological changes were examined microscopically. RESULTS: Vein length, mean diameter, and the amount of tumescence was comparable between the three groups. Histological examination showed extensive vein wall destruction, the least in the outer layer of the vein wall. The total vein wall damage was 9.2/15 (SD 3.5) for EVLA, 13.3/15 (SD 3.3) for RFA, and 11.2/15 (SD 2.8) for SVS group. There was no significant difference among the three groups. Perivenous tissue damage was low. No extrafascial damage was seen. CONCLUSION: Histological findings after steam ablation are similar to the RFA and EVLA with a low perivenous tissue destruction score and a high vein wall destruction score.

The relative value of strain and strain rate for defining intrinsic myocardial function.

It is well accepted that strain and strain rate deformation parameters are not only a measure of intrinsic myocardial contractility but are also influenced by changes in cardiac load and structure. To date, no information is available on the relative importance of these confounders. This study was designed to investigate how strain and strain rate, measured by Doppler echocardiography, relate to the individual factors that determine cardiac performance. Echocardiographic and conductance measurements were simultaneously performed in mice in which individual determinants of cardiac performance were mechanically and/or pharmacologically modulated. A multivariable analysis was performed with radial and circumferential strains and peak systolic radial and circumferential strain rates as dependent parameters and preload recruitable stroke work (PRSW), arterial elastance (E(a)), end-diastolic pressure, and left ventricular myocardial volume (LVMV) as independent factors representing myocardial contractility, afterload, preload, and myocardial volume, respectively. Radial strain was most influenced by E(a) (ß = -0.58, R(2) = 0.34), whereas circumferential strain was strongly associated with E(a) and moderately with LVMV (ß = 0.79 and -0.52, respectively, R(2) = 0.54). Radial strain rate was related to both PRSW and LVMV (ß = 0.79 and -0.62, respectively, R(2) = 0.50), whereas circumferential strain rate showed a prominent correlation only with PRSW (ß = -0.61, R(2) = 0.51). In conclusion, strain (both radial and circumferential) is not a good surrogate measure of intrinsic myocardial contractility unless the strong confounding influence of afterload is considered. Strain rate is a more robust measure of contractility that is less influenced by changes in cardiac load and structure. Thus, peak systolic strain rate is the more relevant parameter to assess myocardial contractile function noninvasively.

Response of mouse brain perfusion to hypo- and hyperventilation measured by arterial spin labeling.

We aimed to setup a noninvasive and well-controlled methodology for evaluation of the cerebrovascular response in mice (C57BL/6J; 12 weeks). Therefore we applied a normo-, hypo-, and hyperventilation paradigm combined with arterial spin labeling and monitoring of the expired CO(2) (expCO(2)) (n=7) or arterial pCO(2) (apCO(2)) (n=12). Reducing the tidal volume by 25% and the respiratory rate by 20% resulted in hypercapnia (apCO(2) from 33 ± 6 mmHg to 64 ± 16 mmHg). Increasing the respiratory rate by 25% and the tidal volume by 20% decreased apCO(2) to 22 ± 5 mmHg. Cerebral blood flow (CBF) was 82 ± 21, 163 ± 41 and 64 ± 18 mL/100 g/min during normo, hypo-, and hyperventilation, respectively (midbrain). The correlation of apCO(2) and CBF levels resulted in a cerebrovascular response of 2.7 ± 0.3, 2.1 ± 0.3, 2.1 ± 0.3, and 3.7 ± 0.5 mL/100 g/min/mmHg for midbrain, cortex, hippocampus and thalamus, respectively. As expCO(2) levels were correlated with apCO(2) (r(2)=0.86; n=4) and CBF (r(2)=0.67) a cerebrovascular response based on simultaneously recorded CBF and expCO(2) levels could be derived (3.3 ± 0.5, 2.5 ± 0.4, 3.0 ± 0.4, and 4.5 ± 0.6 mL/100 g/min/mmHg; order as above). A cross-over experiment resulted in similar responses. In conclusion, this protocol allows evaluating basal CBF and cerebrovascular response in mice under well-controlled conditions by simply changing ventilator settings and correlating CBF with apCO(2) and/or simultaneously obtained expCO(2).

Variation of the clavicle's muscle insertion footprints - a cadaveric study.

The muscle footprint anatomy of the clavicle is described in various anatomical textbooks but research on the footprint variation is rare. Our goal was to assess the variation and to create a probabilistic atlas of the muscle footprint anatomy. 14 right and left clavicles of anatomical specimens were dissected until only muscle fibers remained. 3D models with muscle footprints were made through CT scanning, laser scanning and photogrammetry. Then, for each side, the mean clavicle was calculated and non-rigidly registered to all other cadaveric bones. Muscle footprints were indicated on the mean left and right clavicle through the 1-to-1 mesh correspondence which is achieved by non-rigid registration. Lastly, 2 probabilistic atlases from the clavicle muscle footprints were generated. There was no statistical significant difference between the surface area (absolute and relative), of the originally dissected muscle footprints, of male and female, and left and right anatomical specimens. Visualization of all muscle footprints on the mean clavicle resulted in 72% (right) and 82% (left) coverage of the surface. The Muscle Insertion Footprint of each specimen covered on average 36.9% of the average right and 37.0% of the average left clavicle. The difference between surface coverage by all MIF and the mean surface coverage, shows that the MIF location varies strongly. From the probabilistic atlas we can conclude that no universal clavicle exists. Therefore, patient-specific clavicle fracture fixation plates should be considered to minimally interfere with the MIF. Therefore, patient-specific clavicle fracture fixation plates which minimally interfere with the footprints should be considered.

Lack of the effect of superoxide dismutase and catalase on Na+,K+-ATPase activity in stunned rabbit hearts.

Reactive oxygen species (ROS) have been implicated in the mechanism of postischemic contractile dysfunction, known as myocardial stunning. In this study, we examined protective effects of antioxidant enzymes, superoxide dismutase (SOD) and catalase, against ischemia/reperfusion-induced cardiac dysfunction and inhibition of Na+,K+-ATPase activity. Isolated Langendorff-perfused rabbit hearts were subjected to 15 min of global normothermic ischemia followed by 10 min reperfusion. The hearts treated with SOD plus catalase did not show significant recovery of left ventricular (LV) end-diastolic pressure compared with untreated ischemic reperfused hearts. Treatment with antioxidants had no protective effects on developed LV pressure or its maximal positive and negative first derivatives (+/-LVdP/dt). Myocardial stunning was accompanied by significant loss in sarcolemmal Na+,K+-ATPase activity and thiol group content. Inhibition of enzyme activity and oxidation of SH groups were not prevented by antioxidant enzymes. These results suggest that administration of SOD and catalase in perfusate do not protect significantly against cardiac dysfunction in stunned rabbit myocardium.

[The effect of type II diabetes and the metabolic syndrome on cardiac second window preconditioning]. / Het effect van type ii diabetes en het metabool syndroom op cardiale tweede venster preconditionering.

Preconditioning is the most powerful endogenous mechanism, to protect the heart against ischemic damage. Conflicting data are published whether preconditioning can be induced in case of diabetes and the metabolic syndrome, which are clinically very relevant conditions. If preconditioning could be induced consistently and chronically in this population, an important reduction of surgical morbidity and mortality could be reached. In this project we induced hypoxic preconditioning in mice and used cardiac pressure-conductance catheterisation and infarct size as outcome parameters. In the first part, we found that hypoxic preconditioning was capable to reduce infarct size with 40% and preserve the load-independent parameters with 33% after coronary occlusion. A DKO (double knock-out: ob/ob; LDLR-/-) model for the metabolic syndrome developed a larger infarct size and had a reduced contractility. No preconditioning could be induced in this model. To detect the determing factor of the resistance to preconditioning, we used single knock-out models. A comparable preconditioning effect of wild type mice could be induced in the lipoprotein receptor deficient (LDLR-/-) model for dyslipidemia. The leptin deficient (ob/ob) model, characterized by insulin resistance and abdominal obesity had, identically to the DKO model, a larger infarct size. A second window of preconditioning could be induced, although it was less pronounced than the wild type and LDLR-/- model. Insulin resistance and abdominal obesity could be identified as the major factor in the resistance to preconditioning.

Added diagnostic value and impact on antimicrobial therapy of 16S rRNA PCR and amplicon sequencing on resected heart valves in infective endocarditis: a prospective cohort study.

OBJECTIVES: For adequate management and therapy of infective endocarditis (IE), identification of the causative pathogen is crucial but molecular testing results are not currently included in diagnostic criteria. The added diagnostic value and impact on antimicrobial therapy of 16S rRNA PCR and amplicon sequencing (16S rRNA PCR) performed on excised heart valves from patients with IE was evaluated alongside the effect of pre-operative antibiotics on the performance of blood culture (BC), valve culture (VC) and 16S rRNA PCR. METHODS: All patients undergoing valve surgery for definite or possible IE, according to modified Duke Criteria, were prospectively included from July 2013 up to and including June 2016. RESULTS: In all, 127 patients were included. Sensitivity for detecting the causative micro-organism in 120 post-operative definite IE patients was 26% for VC and 87% for BC and 16S rRNA PCR. 16S rRNA PCR, VC and BC were equally sensitive for different valve types and causative pathogens. In 27 (21%) definite IE patients, 16S rRNA PCR clarified discrepant culture results or was the only method identifying the causative pathogen. In 12 (10%) post-operative definite IE cases, molecular testing results influenced antimicrobial therapy. CONCLUSIONS: The very good performance characteristics, added diagnostic value and impact on antimicrobial therapy of molecular testing of heart valves should support the incorporation of molecular testing in diagnostic criteria and guidelines for IE.

Evolving trends in infective endocarditis.

Infective endocarditis is a microbial infection of the endocardial surface and, despite improvements in diagnostic accuracy, medical therapy and surgical techniques, mortality remains high. This review focuses on changes in epidemiology, microbiology and diagnosis, as well as changes in medical and surgical management of infective endocarditis affecting native and prosthetic valves in adults, that have evolved during the past two decades. Significant changes have included an increasing involvement of prosthetic valves and nosocomially-acquired disease, an increased involvement of staphylococci as the causative agents, and a recognition that elderly individuals with degenerative valvular disease are the most vulnerable population. Topics still requiring study include whether and when valve replacement should be performed, and how to predict perivalvular complications or embolisation based on echocardiography findings. Optimisation of antimicrobial treatment schemes (choice of the antibiotic, dose and duration) also requires further investigation.

The effect of brain death on cardiovascular function in rats. Part II. The cause of the in vivo haemodynamic changes.

OBJECTIVE: Brain death-induced haemodynamic collapse in rats is not caused by intrinsic myocardial damage as shown in the accompanying paper. We investigated whether this collapse could be caused by the withdrawal of the basal adrenergic tone. METHODS: Heart rate and blood pressure variability was studied in rats before and after brain death. The effect of high doses of phentolamine, propranolol or their combination administered before or after brain death was assessed. RESULTS: Heart rate variability in the respiratory frequency range significantly increased, whereas in the low-frequency range it tended to decrease after brain death. Systolic and diastolic blood pressure variability up to 0.18 Hz largely disappeared, but stayed unchanged in the respiratory frequency range. High-dose combined phentolamine and propranolol pretreatment induced a haemodynamic picture comparable to the situation seen after brain death without pharmacological intervention. Brain death did not further deteriorate the haemodynamic situation after combined pretreatment. On the other hand, once the haemodynamic collapse after brain death had settled, adrenergic blockade had no important influence any more. CONCLUSION: We conclude that the haemodynamic situation seen after brain death is one of profound sympathetic withdrawal.

The effect of brain death on cardiovascular function in rats. Part I. Is the heart damaged?

OBJECTIVE: Brain death induces important haemodynamic changes in rats, with a drop in arterial blood pressure, left ventricular developed pressure and dP/dtmax to less than 50% of its control value. Myocardial damage was reported to contribute to this paradigm. The role of potential underlying pathogenetic mechanisms, such as a circulating cardiodepressant factor, NO, endogenous opioid peptides, vagal or beta-adrenergic activation, or hypophyseal dysfunction, were explored, but none of them could be demonstrated as the culprit. This study investigated whether functionally important intrinsic myocardial damage was induced by brain death in the rat, and whether coronary endothelial cell dysfunction, possibly causing multifocal ischaemia, contributed to this. METHODS: Brain death was induced in rats by sudden inflation of an intracranial balloon. Extensive haemodynamic measurements, including heart rate, arterial blood pressure central venous pressure, left ventricular pressure, and cardiac output, were performed. Hearts excised 1 and 4 h after brain death were examined histologically. The contractile reserve of these hearts was tested by administration of increasing doses of adrenaline (10(-9) to 10(-6) mol/l) in a Langendorff system. The coronary endothelium was tested with regard to its barrier function for macromolecules by determining the extravasation of injected Evans blue, and with regard to its vasoactive function by testing the effects of serotonin and nitroglycerin in a Langendorff system. RESULTS: The haemodynamic measurements suggested that the cardiovascular collapse consisted mainly in alterations in afterload. Contractile reserve, as tested with increasing adrenaline doses, revealed a normal dose-response curve. No histological myocardial damage was found after brain death in rats. No abnormal extravasation of Evans blue was seen. Coronary vasoreactivity towards nitroglycerin and serotonin was normal. CONCLUSION: Myocardial damage, if present at all, contributes only minimally to the changes in haemodynamic profile seen after brain death in the rat, and the coronary endothelium appears to preserve its barrier and vasoactive function.

Post-operative echocardiographic evaluation of bioprosthetic mitral valve implantation in sheep.

The ovine model is generally considered to be the best for testing bioprosthetic heart valve durability. Although echocardiography is the method of choice for the interim evaluation of the valve, literature on sheep echocardiography is scarce. Within the context of a study on treatment of pericardial heart valve prostheses, 19 adolescent sheep underwent transthoracic echocardiography six days after mitral implantation of bioprosthetic valves. Echocardiographic examination was performed under mild anesthesia and animals were put in a right lateral decubitus position. Four images were obtained: right parasternal long axis four and five chamber views, right parasternal long axis view with left ventricular outflow, and right parasternal short axis view through the mitral valve. We measured aortic annulus and velocity time integral over the aortic valve to determine stroke volume, cardiac output and cardiac index. The mitral valve was evaluated through color Doppler imaging for valvular and paravalvular leakages. Pulsed wave spectral Doppler was used for the measurement of velocities, pressures and velocity time integrals. For the evaluation of valve stenosis deceleration time and pressure half-time were determined. Effective orifice area of the mitral valve was derived. And, although not measured, other structures could clearly be visualized: right and left ventricle and atrium, wall thicknesses, tricuspid valve. This study shows that echocardiography in sheep is feasible, and that right parasternal images, obtained in animals in a right lateral decubitus position, are well qualified for the interim evaluation of bioprosthetic valves implanted in the mitral position. Besides the implanted valve, other cardiac structures like atria and ventricles can be visualized and evaluated.

Automated Delineation of Vessel Wall and Thrombus Boundaries of Abdominal Aortic Aneurysms Using Multispectral MR Images.

A correct patient-specific identification of the abdominal aortic aneurysm is useful for both diagnosis and treatment stages, as it locates the disease and represents its geometry. The actual thickness and shape of the arterial wall and the intraluminal thrombus are of great importance when predicting the rupture of the abdominal aortic aneurysms. The authors describe a novel method for delineating both the internal and external contours of the aortic wall, which allows distinguishing between vessel wall and intraluminal thrombus. The method is based on active shape model and texture statistical information. The method was validated with eight MR patient studies. There was high correspondence between automatic and manual measurements for the vessel wall area. Resulting segmented images presented a mean Dice coefficient with respect to manual segmentations of 0.88 and a mean modified Hausdorff distance of 1.14 mm for the internal face and 0.86 and 1.33 mm for the external face of the arterial wall. Preliminary results of the segmentation show high correspondence between automatic and manual measurements for the vessel wall and thrombus areas. However, since the dataset is small the conclusions cannot be generalized.

Changes in organ perfusion after brain death in the rat and its relation to circulating catecholamines.

Brain death can have an impact on donor organ function. This is often attributed to an altered hormonal, mainly thyroidal, status after brain death. A second possible explanation is that during the brain death process, blood flow is redistributed, causing ischemic damage in underperfused organs or regions. We investigated blood flow redistribution with colored microspheres in the rat early and late after brain death, induced by inflation of an intracranial balloon, and correlated this with the global hemodynamic situation and plasma catecholamine concentrations. Brain death was proven by the demonstration of lasting absence of brain perfusion in all animals. Myocardial blood flow closely followed the myocardial oxygen need as estimated by the rate-pressure product. The abdominal organs showed intense vasoconstriction early after brain death, which led to significantly decreased perfusion of these organs despite the highly increased perfusion pressure, followed by significant vasodilation. Total plasma catecholamine concentration was 57 times higher at 30 sec after brain death as compared with basal levels. Plasma noradrenaline concentration fell significantly below basal levels late after brain death. We conclude that brain death importantly alters regional perfusion, with possible implications for donor organ function. These changes are probably due to the tremendous alterations in the activity of the sympathetic nervous system.

Mechanical support with microaxial blood pumps for postcardiotomy left ventricular failure: can outcome be predicted?

OBJECTIVE: We sought to identify the indications of mechanical support in postcardiotomy left ventricular failure in patients who are unable to undergo transplantation. METHODS: From 1989 through 1997, 61 patients with postcardiotomy left ventricular failure beyond intra-aortic balloon pumping were assisted with the Hemopump cardiac assist system (Medtronic, Minneapolis, Minn). Their mean age was 64 +/- 8 years. Comorbidity was prevalent; 47% underwent cardiac massage before pump support, and evolving myocardial infarction was diagnosed in 43% before surgery. Multivariable logistic regression of data known at the moment of pump insertion was performed to identify the risk factors for mortality. RESULTS: Sixty-five percent of the patients were weaned from the device, but only 30% were discharged home. Cardiac index evolution during the first hours after pump insertion (P <.001) is the only independent predictor for possibility to wean from the device in the multivariable analysis. Acute renal failure is the only variable retained in the model for 90-day mortality. Device-related complications were far more frequent with the femoral (54%) than with the transthoracic (6%) cannula. Only 13% of the patients had bleeding complications. CONCLUSIONS: One third of the patients with postcardiotomy heart failure refractory to use of the intra-aortic balloon pump can be saved with the use of an endovascular axial flow pump. It is impossible to predict lethal outcome on preoperative data alone. The early hemodynamic response to support seems to be related to functional recovery of the heart and subsequent weaning from the device.

Na+/H+ exchange inhibition improves long-term myocardial preservation.

BACKGROUND: Na+/H+ exchange plays an important role in the ionic changes observed during myocardial ischemia and reperfusion. We investigated the cardioprotective efficacy of a selective Na+/H+ exchange inhibitor, 4-isopropyl-3-methylsulfonyl-benzoylguanidin-methanesulfonate (HOE642), in a canine model of long-term heart preservation. METHODS: Canine donor hearts were stored for 24 hours in hyperkalemic crystalloid cardioplegic solution; in cardioplegic solution enriched with HOE642; in cardioplegic solution enriched with HOE642, with donor and recipient treated with HOE642; in standard cardioplegic solution, with donor and recipient treated with HOE642; or in standard cardioplegic solution, with only the recipient treated. After orthotopic transplantation, pressure-volume relationships were obtained and dogs were weaned from bypass. Morphology was studied. RESULTS: Myocardial compliance was well preserved when donor and recipient were treated. These groups had the lowest myocardial water content, and no morphologic signs of irreversible damage. In these groups, weaning from cardiopulmonary bypass was successful in 10 of 10 animals, with a cardiac index around 2 L x min(-1) x m(-2). Only 3 of 5 animals in each of the other three groups could be weaned, with significantly lower cardiac indices. CONCLUSIONS: Treatment with HOE642 in both donor and recipient improves myocardial compliance, postweaning cardiac index, and ultrastructure of donor hearts preserved for 24 hours and orthotopically transplanted.

Determinants of early and late results of combined valve operations and coronary artery bypass grafting.

BACKGROUND: Factors determining the outcome of operative correction of valvular abnormalities combined with coronary artery bypass grafting are still incompletely defined. METHODS: Determinants of early and late (more than 90 days) deaths and event-free survival were studied for combined valve operations and coronary artery bypass grafting in 741 patients using multivariate analysis. RESULTS: Ninety-day survival probability was 89% (95% confidence interval, 87% to 92%). Preoperative risk factors for early death were age, female sex, renal failure, New York Heart Association class IV or V, and mitral insufficiency. The operative risk factor was the duration of aortic cross-clamping. Five- and 10-year survival probabilities were 74% (95% confidence interval, 71% to 78%) and 43% (95% confidence interval, 36% to 50%), respectively. Preoperative risk factors for late death were age, preoperative renal failure, New York Heart Association class IV or V, vessel disease, and nonsinus rhythm. Five- and 10-year event-free survival probabilities were 57% (95% confidence interval, 53% to 61%) and 23% (95% confidence interval, 17% to 28%), respectively. Preoperative risk factors for non-event-free survival were age, female sex, reduced left ventricular function, mitral regurgitation, and pacemaker rhythm. CONCLUSION: The demographic factors of age and female sex; the comorbid condition of renal failure; the cardiac conditions of advanced New York Heart Association class, left ventricular function, mitral regurgitation, vessel disease, and cardiac rhythm; and the operative condition of ischemia time are the most important predictors of clinical outcome after combined valve operations and coronary artery bypass grafting.

Calcification characteristics of porcine stented valves in a juvenile sheep model.

BACKGROUND: Different antimineralization treatments of stented porcine bioprostheses were evaluated: ethanol (Epic), alpha-amino-oleic acid (AOA) (Mosaic), and sodium dodecyl sulfate (SDS) (Hancock II). A nontreated, glutaraldehyde-fixed valve (Labcor) served as control. METHODS: For each treatment, six valves were implanted in juvenile sheep in the pulmonary position. Valves were explanted after 3 and 6 months and examined macroscopically, by roentgenogram and light and transmission electron microscopy. Calcium content (microg/mg) was determined by atomic absorption spectrometry. RESULTS: The Labcor valves revealed small calcium deposits in the cusps, although calcium content remained low (median value 0.4+/-0.8 microg/mg). SDS did not prevent cusp calcification as assessed by histology and calcium content measurement, which was higher than in all other valves: 1.9+/-4.6 microg/mg (p < 0.05). Cusp retraction and rupture were occasionally found in the Hancock. The Mosaic and Epic valves showed no cusp calcification and had low calcium contents (0.3+/-2.4 microg/mg and 0.7+/-0.6 microg/mg, respectively). Epic showed less pannus formation, but had hematoma or iron staining in the cusps. CONCLUSIONS: SDS is inefficient as an antimineralization treatment, in contrast to ethanol or AOA. Cusp hematoma after ethanol treatment needs further investigation.

Fifteen-year experience with the mitral Carpentier-Edwards PERIMOUNT pericardial bioprosthesis.

BACKGROUND: This multicenter study concerning the mitral PERIMOUNT valve previously reported clinical results at 12 years; this report updates the performance to 15 years postoperatively. METHODS: The 435 patients (mean age 60.7+/-11.6 years; 41.1% male) underwent implantation with the PERIMOUNT valve between 1984 and 1989 at seven institutions. Follow-up was complete for 96.1% of the cohort. The mean follow-up was 8.1+/-4.4 years (range 0 to 15.4 years) for a total of 3492 patient-years. RESULTS: There were 34 (7.8%) operative deaths, one (0.2%) valve related. The late mortality rate was 5.3%/patient-year (2.2%/patient-year valve related). At 14 years, the overall actuarial survival rate was 37.1%+/-3.3% (63.1%+/-4.4% valve related). Actuarial freedom from complications at 14 years was as follows: thromboembolism, 83.8%+/-3.2% (1.1%/patient-year); hemorrhage, 86.6%+/-3.2% (1.1%/patient-year); and explant due to structural valve deterioration (SVD), 68.8%+/-4.7%. Actual freedom from explant due to SVD was 83.4%+/-2.3%. Rates of structural failure decreased with increasing age at implant. CONCLUSIONS: The Carpentier-Edwards PERIMOUNT Pericardial Bioprosthesis is a reliable choice for a tissue valve in the mitral position, especially in patients more than 60 years of age.